1. Technical Field
The present disclosure relates to lens systems, and particularly to an internally focusing lens system in which focusing is accomplished by moving an inner lens group or groups within the whole lens system.
2. Description of Related Art
In a typical image-taking apparatus such as a camera in a mobile phone, there is an article called a macro lens or a micro lens (hereinafter referred to as a “macro lens”). Among image pickup systems in general, the macro lens is mainly used for close-up photography. In a typical macro lens system, focusing is performed by moving the entire lens unit or some lenses at ends of the lens unit toward or away from an object side. Hence, the overall length occupied by the lens unit changes. This limits design options, particularly design options directed towards more compact camera units.
Therefore, a lens system that can overcome the above-described deficiencies is desired.